Injection device

ABSTRACT

An injection device includes a housing having a receptacle for a vessel for holding injection fluid; an operator-manipulated element for setting an injection dose; a dosing member rotatable about a longitudinal center axis relative to the housing when setting the injection dose; a feed part; and, a latching unit acting between the feed part and housing. The dosing member has a zero position whereat no dose is set and an injection position whereat an intended dose of injection fluid is set. A spring acts between the dosing member and the housing to return the dosing member from an intermediate position to the injection position or a zero position.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of international patentapplication PCT/EP2014/000313, filed Feb. 5, 2014, designating theUnited States and claiming priority from German application 20 2013 001350.8, filed Feb. 8, 2013, and the entire content of both applicationsis incorporated herein by reference.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 8,747,367 discloses an injection device in which, in orderto set an injection dose, a dosing member is rotated until the desireddose appears in a window. On account of the rotation, the dosing membermoves in the distal direction of the injection device, that is, movesaway from an injection needle placed on the injection device. Theinjection device has a latching device which has a multiplicity oflatching positions. As a result, the user can also set the dose bycounting a number of palpable or audible latching positions. It is notpossible to set intermediate positions between two latching positions.The injection device can have a torsion spring which is without functionwhen setting a dose. When ejecting a set dose from the container, thetorsion spring supports the rotation of the setting member and thus theinjection.

With the injection device shown in U.S. Pat. No. 8,747,367, a widevariety of quantities of injection fluid can be set. The possiblequantities to be set are defined by the latching device. The operatingelement jumps into the nearest intended position from positions of theoperating element which correspond to quantities of injection fluid thatare not intended by the manufacturer.

In order that the operating button jumps automatically and reliably froman intermediate position into a latching position, the catch has to besufficiently strong and the radial latching positions must be locatedclose enough together. However, the strength of latching influences thetorque which the user has to apply in order to rotate the operatingbutton and set the dose. The structurally possible spacing of thelatching positions is largely defined thereby and can be adapted to theapplication case only within narrow bounds.

SUMMARY OF THE INVENTION

It is an object of the invention to provide an injection device in whichonly defined quantities of injection fluid can be ejected from thecontainer and which allows ready adaptation to the desired applicationcase.

This object is achieved by an injection device having an injectiondevice defining a longitudinal center axis and comprising: a housinghaving a receptacle formed therein for a vessel for holding injectionfluid; an operator-manipulated element for setting an injection dose; adosing member configured to be rotated about the longitudinal centeraxis relative to the housing when setting the injection dose; the dosingmember having a zero position whereat no dose is set and at least oneinjection position whereat an intended dose of injection fluid is set; afeed part; a latching unit configured to act between the feed part andthe housing; the feed part being rotatable about the longitudinal centeraxis for setting an injection dose; the feed part further beingconnected to the dosing member in a rotationally fixed manner so as torotate therewith during the setting of the injection dose; the housinghaving at least one longitudinal rib; the feed part being configured tomove in the direction of the longitudinal center axis with respect tothe housing during an ejection of the dose and to be guided on the atleast one longitudinal rib; the latching unit having at least onelatching element being formed on the longitudinal rib; the latching unitincluding at least one latching position corresponding to the injectionposition; the dosing member being positionable in at least oneintermediate position whereat no intended dose of injection fluid isset; and, a spring configured to act between the dosing member and thehousing so as to return the dosing member, when the operator-manipulatedelement is unactuated, from the intermediate position to the at leastone injection position or the zero position.

The dosing member has at least one injection position in which a dose,intended by the manufacturer, of injection fluid is set. In this case,it is possible for only one injection position to be provided when amedicament is to be administered which is intended to be administeredonly in a defined dose. However, it is also possible for a plurality ofinjection positions to be provided, for example when a medicament can beadministered in a plurality of different defined doses depending onindication and user. The injection device has a latching device, whereineach injection position of the dosing member is assigned a latchingposition of the latching device. Depending on the configuration of thelatching device, the force exerted on the dosing member by the latchingdevice can be too small to restore the dosing member automatically andsecurely into the zero position or an injection position from eachintermediate position between the zero position and the injectionposition, or from each intermediate position between two injectionpositions. In order, in the case of an injection device in which thedosing member can be set in an intermediate position on account of theconfiguration of the latching device, to avoid the situation in which auser can inject a dose that is not intended, that is, a dose whichcorresponds to an intermediate position, a spring acts between thedosing member and the housing. As soon as the user releases theoperating element in an intermediate position of the dosing member, thedosing member is restored by the spring from the intermediate positioninto an injection position or the zero position. The injection positionand the zero position are intended positions of the dosing member.Advantageously, the dosing member is restored into the next lowestintended position so that accidental injection of too high a dose isavoided.

In conventional injection devices, the setting of the injection dose andthe ejection of the injection fluid take place in different operatingmovements. Between these operating movements, the user usually has torelease the operating element. By way of the spring, the dosing membercan be restored easily into the next lowest intended position when theuser releases the operating element after setting the injection dose andbefore ejecting the injection fluid from the container.

The dosing member is rotatable about a longitudinal center axis of theinjection device in order to set an injection dose. This results in acompact structure and easy handling.

The latching device acts between a feed part and the housing, whereinthe feed part is rotatable about the longitudinal center axis of theinjection device in order to set an injection dose. The feed part isconnected to the dosing member in a rotationally fixed manner during thesetting of an injection dose. The feed part moves in the direction ofthe longitudinal center axis with respect to the housing during theejection of the dose. As a result, the latching device does not actduring the ejection of the injection fluid and no latching steps areaudible or palpable to the user. The latching device can furthermore beconfigured such that it is no longer possible to rotate the feed partback into the next lowest injection position after an injection positionhas been reached. A simple structure arises in that the feed part isguided on at least one longitudinal rib of the housing. At least onelatching element of the latching device is formed on the longitudinalrib. This results in a simple structure. The longitudinal ribsimultaneously forms a latching element and the longitudinal guide forthe feed part.

Advantageously, the spring is tensioned during the setting of aninjection dose. However, provision can also be made for the spring to belargely relaxed in the zero position of the dosing member. The springacts in particular between the dosing member and the housing.Advantageously, the spring is connected directly to the dosing memberand the housing. This results in a favorable installation situation.Particularly advantageously, the spring is a coil spring, wherein afirst end of the spring is mounted on the dosing member and a second endof the spring is mounted on the housing. However, provision can also bemade for one end of the spring to be fixed to a component held in thehousing in a rotationally fixed manner. This can result in a simplifiedstructure of the individual parts of the injection device.

The latching device advantageously provides audible and/or palpablefeedback for the user when an injection position is reached.Advantageously, the latching device does not exert any force on thedosing member in intermediate positions of the dosing member. Thus, therestoration of the dosing member into an injection position or the zeroposition does not take place counter to a force exerted by the latchingdevice. As a result, easy and reliable restoration is achieved, sincethe restoration force exerted by the spring is not superimposed with aforce exerted by the latching device. Since the latching device does notexert any force on the dosing member in intermediate positions of thedosing member, defined latching positions can furthermore be achievedeven when there is little available installation space. A simplestructure arises when the latching device has at least one resilientcatch which cooperates with a latching element.

In the case of a rotatable dosing member, provision is made for theinjection positions to be at an angular spacing of at least 30° from oneanother in the circumferential direction about the longitudinal centeraxis. At angular spacings of about 30° or more, restoration intointended positions of the dosing member can no longer be reliablyensured simply on account of the geometric configuration of the latchingdevice. The angular spacing between two injection positions isadvantageously at least about 45°, in particular at least about 60°. Theangular spacing is advantageously selected such that an integer multipleof the angular spacing results in 360°.

The operating element is advantageously configured in a multipart mannerand comprises an actuating button and the adjustment sleeve. Theadjustment sleeve is connected fixedly to the dosing member. Theactuating button is advantageously connected to the feed part via anentrainer, wherein the actuating button is moved in the direction of thelongitudinal center axis in the proximal direction of the injectiondevice in order to eject injection fluid from the container. Thisresults in simple, intuitive operation of the injection device. The“proximal direction” denotes in this case the injection direction, thatis, in the direction toward a receptacle for the injection needle, orthe direction in which the injection fluid is ejected from thecontainer. The “distal direction” denotes the opposite direction, thatis, away from the injection needle. The distal end of the injectiondevice is the end that is remote from the injection needle. The term“proximal” denotes that side of the injection device that faces thepuncture site during an injection, and “distal” means the side which isremote from the puncture site. A simple configuration of the injectiondevice results when the actuating button is formed in one piece with theentrainer. However, provision can also be made for the entrainer to beconnected to the actuating button in an axially fixed manner but so asto be rotatable with respect to the actuating button.

The actuating button is advantageously connected to the adjustmentsleeve via a coupling, which establishes a rotationally fixed connectionbetween the entrainer and the adjustment sleeve in a first, distalposition of the actuating button, and allows the adjustment sleeve torotate with respect to the entrainer in a second, proximal position ofthe actuating button. As a result, it is possible for the feed part torotate together with the dosing member during the setting of theinjection dose and to be guided in the longitudinal direction of theinjection device and not to be rotatable with respect to the housing,while the dosing member rotates about the longitudinal center axis ofthe injection device, during the ejection of the injection fluid out ofthe container. The rotary movement of the feed part advantageouslybrings about an axial movement of the feed part by a first travel in thedirection of the longitudinal center axis of the injection device via afirst threaded connection during the setting of the injection dose. Inthis case, the feed part is advantageously moved in the distaldirection.

A simple structure results, in a first embodiment of the injectiondevice, when the dosing member is mounted in the housing in a rotatablemanner and so as to be immovable in the direction of the longitudinalcenter axis. This is advantageous in particular for injection devices inwhich the dosing member should be rotated by less than one revolutionwith respect to the housing in order to set the maximum dose.Advantageously, the injection device has a slide which bears a thread ofa second threaded connection. The rotary movement of the slide in thiscase brings about a movement in the distal direction of the longitudinalcenter axis by a second travel. The second travel, by which the slidemoves, is advantageously at least as large as the first travel, by whichthe feed part moves.

In order to allow precise setting of an injection dose, provision isadvantageously made, in a further embodiment of the injection device,for the dosing member to move in the direction of the longitudinalcenter axis of the injection device, preferably in the distal direction,during the setting of an injection dose, and for the movements of thefeed part and dosing member in the direction of the longitudinal centeraxis of the injection device to differ from one another. The dosingmember is advantageously connected to the housing via a second threadedconnection, which brings about the rotary movement of the dosing memberinto a movement of the dosing member and of the operating element in thedirection of the longitudinal center axis of the injection device by asecond travel. The second travel, by which the dosing member moves, isin this case greater than the first travel, by which the feed partmoves. The dosing member, too, advantageously moves in the distaldirection in this case. Advantageously, the injection device has a slidewhich bears a thread of a third threaded connection. The rotary movementof the slide in this case brings about a movement in the distaldirection of the longitudinal center axis by a third travel. The thirdtravel, by which the slide moves, is advantageously at least as large asthe first travel, by which the feed part moves. The slide has inparticular a driving ledge which cooperates with a driving ledge of thefeed part. As a result, the slide can act on the feed part and move thelatter in the proximal direction during the ejection of the injectionfluid.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the drawingswherein:

FIG. 1 shows a side view of one embodiment of an injection device;

FIG. 2 shows a section along the line II-II in FIG. 1;

FIG. 3 shows a portion of the injection device from FIG. 1 following thesetting of a non-intended quantity of injection fluid;

FIG. 4 shows the injection device from FIG. 1 following the setting ofan intended quantity, to be ejected, of injection fluid;

FIG. 5 shows a section along the line V-V in FIG. 4;

FIG. 6 shows an enlarged illustration of the distal housing part of theinjection device from FIG. 2;

FIG. 7 shows a sectional illustration of a detail of the injectiondevice from FIG. 5 in the region of the operating element after theactuating button has been pressed;

FIG. 8 shows a side view of the injection device with the housingremoved;

FIG. 9 shows a side view of the entrainer of the injection device;

FIG. 10 shows a section along the line X-X in FIG. 9;

FIG. 11 shows a section along the line XI-XI in FIG. 9;

FIG. 12 shows a side view of the dosing member of the injection device;

FIG. 13 shows a section along the line XIII-XIII in FIG. 12;

FIG. 14 shows a side view of the dosing member in the direction of thearrow XIV in FIG. 12;

FIG. 15 shows a side view of an internal tube of the injection device;

FIG. 16 shows a section along the line XVI-XVI in FIG. 15;

FIG. 17 shows an enlarged illustration of the detail XVII in FIG. 16;

FIG. 18 shows a side view of the slide of the injection device;

FIG. 19 shows a section along the line XIX-XIX in FIG. 18;

FIG. 20 shows a section along the line XX-XX in FIG. 18;

FIG. 21 shows a side view of the feed part of the injection device;

FIG. 22 shows a section along the line XXII-XXII in FIG. 21;

FIG. 23 shows a section along the line XXIII-XXIII in FIG. 21;

FIG. 24 shows a side view of the feed part in the direction of the arrowXXIV in FIG. 21;

FIG. 25 shows a side view of the piston rod of the dosing piston of theinjection device;

FIG. 26 shows a side view in the direction of the arrow XXVI in FIG. 25;

FIG. 27 shows a section through the internal tube at the level of theline XXVII-XXVII in FIG. 15 with the feed part, arranged therein, in thelocked position of the operating element;

FIG. 28 shows a sectional illustration corresponding to FIG. 27 with thefeed part in the injection position of the operating element;

FIG. 29 shows a side view of a further embodiment of injection device;

FIG. 30 shows a sectional illustration of a detail of the injectiondevice from FIG. 29 along the line XXX-XXX in FIG. 29;

FIG. 31 shows a side view of the injection device from FIG. 1 followingthe setting of an intended quantity, to be ejected, of injection fluid;

FIG. 32 shows a sectional illustration of a detail of the injectiondevice from FIG. 31 along the line XXXII-XXXII in FIG. 31;

FIG. 33 shows a sectional illustration of a detail of the injectiondevice from FIG. 31 along the line XXXII-XXXII in FIG. 31 after theactuating button has been pressed;

FIG. 34 shows a side view of the injection device with the housingremoved;

FIG. 35 shows a side view in the direction of the arrow XXXV in FIG. 34;

FIG. 36 shows a side view in the direction of the arrow XXXVI in FIG.35;

FIG. 37 shows a perspective illustration of the dosing member of theinjection device from FIG. 29;

FIG. 38 shows a side view of the dosing member from FIG. 37;

FIG. 39 shows a section along the line XXXIX-XXXIX in FIG. 38;

FIG. 40 shows a side view in the direction of the arrow XL in FIG. 38;

FIG. 41 shows a side view of the scale of the dosing member from FIG.37;

FIG. 42 shows a side view in the direction of the arrow XLII in FIG. 41;

FIG. 43 shows a side view of the scale of one embodiment of the dosingmember;

FIG. 44 shows a side view in the direction of the arrow XLIV in FIG. 43;

FIG. 45 shows a side view in the direction of the arrow XLV in FIG. 44;

FIG. 46 shows a perspective illustration of the actuating button of theinjection device from FIG. 29;

FIG. 47 shows a side view of the actuating button from FIG. 46;

FIG. 48 shows a section along the line XLVIII-XLVIII in FIG. 47;

FIG. 49 shows a section along the line XLIX-XLIX in FIG. 47;

FIG. 50 shows a perspective illustration of the piston rod ring of theinjection device from FIG. 29;

FIG. 51 shows a side view of the piston rod ring from FIG. 50;

FIG. 52 shows a side view in the direction of the arrow LII-LII in FIG.51;

FIG. 53 shows a view from above in the direction of the arrow LIII-LIIIin FIG. 51;

FIG. 54 shows a perspective illustration of one embodiment of a pistonrod ring of the injection device from FIG. 29;

FIG. 55 shows a view of the piston rod ring from FIG. 54 from above;

FIG. 56 shows a perspective illustration of the slide of the injectiondevice from FIG. 29;

FIG. 57 shows a side view of the slide from FIG. 56;

FIG. 58 shows a side view in the direction of the arrow LVIII in FIG.57;

FIGS. 59 and 60 show perspective illustrations of the feed part of theinjection device from FIG. 29;

FIG. 61 shows a side view of the feed part in FIGS. 59 and 60;

FIG. 62 shows a section along the line LXII-LXII in FIG. 61;

FIG. 63 shows a side view in the direction of the arrow LXIII in FIG.61;

FIG. 64 shows a side view of the upper housing part of the injectiondevice from FIG. 29;

FIG. 65 shows a section along the line LXV-LXV in FIG. 64;

FIG. 66 shows a section along the line LXVI-LXVI in FIG. 65;

FIG. 67 shows a side view of the injection device from FIG. 29 followingthe setting of a non-intended quantity of injection fluid;

FIG. 68 shows a section along the line LXVIII-LXVIII in FIG. 67;

FIG. 69 shows a side view of the injection device from FIG. 29 followingthe setting of an intended quantity, to be ejected, of injection fluid;and,

FIG. 70 shows a section along the line LXX-LXX in FIG. 69.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

The injection device 1 shown in FIG. 1 has a housing 2, which comprisesan upper, distal housing part 3 and a holder 4 arranged on the proximalside of the upper housing part 3. At its proximal end, the holder 4 hasan external thread 29 on which an injection needle 81, schematicallyshown in FIG. 1, can be screwed. Formed in the holder 4 is a receptacle5, shown in FIG. 2, for a container or vessel containing injectionfluid. The container containing injection fluid is not shown in thefigures for the first embodiment. As FIG. 1 shows, the holder 4 has atleast one cutout 10, through which the container containing injectionfluid is visible. As a result, the user can easily identify whetherinjection fluid is still present in the container. As FIG. 2 shows, twocutouts 10 that are arranged opposite one another are provided on theholder 4.

As FIG. 1 shows, an operating element 6, which has an adjustment sleeve7 and an actuating button 8 arranged on the distal side of theadjustment sleeve 7, is arranged at the distal end of the housing part3. Adjacently to the adjustment sleeve 7, the housing part 3 has awindow 9 through which a scale applied to a dosing member 16 isdiscernible. The dosing member 16 is arranged in the housing part 3. InFIG. 1, the scale shows a “0”, which signals to the user that a quantityhas not been set. The dosing member 16 is in a zero position 85, inwhich no dose is set.

FIG. 2 shows the structure of the injection device 1 in detail. Theinjection device 1 has an entrainer 13, which is configured in asubstantially sleeve-like manner and is fixedly connected axially to theactuating button 8 of the operating element 6. The term “axial” relatesin each case to the direction of a longitudinal center axis 50 of theinjection device 1, here. The actuating button 8 is connected to theentrainer 13 via a snap connection which allows the actuating button 8to rotate with respect to the entrainer 13. The entrainer 13 isconnected to the adjustment sleeve 7 of the operating element 6 via acoupling 14. In the first, distal position 71, shown in FIG. 2, of theactuating button 8, the coupling 14 is closed. The adjustment sleeve 7of the operating element 6 is connected to the entrainer 13 in arotationally fixed manner. The adjustment sleeve 7 is fixedly connectedto the dosing member 16, which is also referred to as setting member orscale tube. The entrainer 13 is connected to a feed part 20 in arotationally fixed manner, the feed part 20 being connected to a pistonrod 23 of a dosing piston 22 by a first threaded connection 25. Thepiston rod 23 bears at its proximal end a piston disk 24, which servesfor abutment against a stopper of the container containing injectionfluid, and via which the injection fluid is ejected from the container.

The piston rod 23 is held in a rotationally fixed manner in a piston rodring 30. The piston rod ring 30 is arranged in an axially movable mannerin the injection device 1. In the position shown in FIG. 2, when nocontainer has been inserted into the receptacle 5, the piston rod ring30 is pushed into its proximal position by a compression spring 31. Inthis position, the piston rod ring 30 is rotatable with respect to thehousing part 3. If a container is inserted into the receptacle 5 and theholder is connected to the housing part 3 by way of a fastening thread11, then the container pushes the piston rod ring 30 in the distaldirection. The injection device 1 has an internal tube 17, which is partof the housing 2 and is connected to the housing part in a rotationallyfixed manner and fixedly in the axial direction. At its distal end, thepiston rod ring 30 has a contour which is coordinated with a contour ofthe internal tube 17. In its distal position, the piston rod ring 30 isconnected in a rotationally fixed manner to the internal tube 17, andthus also in a rotationally fixed manner to the housing part 3, via thecontours. With a container inserted into the receptacle 5, the pistonrod 23 is held in the housing part 3 in a rotationally fixed mannerthereby. As a result of the rotationally fixed connection of the pistonrod 23 and housing part 3, a rotation of the feed part 20 brings about amovement of the feed part 20 in the distal direction, that is, in thedirection of the arrow 75 in FIG. 2. Formed between the feed part 20 andthe internal tube 17 is a latching connection device 26 which defineslatching positions of the feed part 20. In the position, shown in FIG.2, of the feed part 20, the feed part 20 bears against a stop 28 formedon the internal tube 17, the stop defining the position of the feed part20 in the axial direction.

The dosing member 16 is connected to the internal tube 17 via a secondthreaded connection 18. The internal tube 17 is fixedly connected to thehousing part 3. The internal tube 17 could also be formed in one piecewith the housing part 3, but as a result, the production of theinjection device 1 becomes very complicated. The dosing member 16 isconnected in a rotationally fixed and axially movable manner to a slide19, which projects into the interior of the dosing member 16. The slide19 is connected to the internal tube 17 via a third threaded connection21. Between the entrainer 13 and the dosing member 16 there acts acompression spring 15, which presses the actuating button 8 into itsfirst position 71. Between the dosing member 16 and the housing 3 thereacts a spring 82. The spring 82 is advantageously configured as atorsion spring. In the embodiment, the spring 82 is a helical tensionspring, which is both elongated and rotated about the longitudinalcenter axis 50 of the injection device 1 during the setting of aninjection dose.

In order to set the quantity of injection fluid to be ejected, the userrotates the operating element 6 until the desired dose appears in thewindow 9. In the process, the adjustment sleeve 7 rotates. The dosingmember 16, which is connected in a rotationally fixed manner to theadjustment sleeve 7, rotates as a result with respect to the upperhousing part 3 and the internal tube 17. On account of its rotarymovement, the dosing member 16 is pushed in the distal direction, thatis, in the direction of the arrow 75, via the second threaded connection18. The operating element 6 and the entrainer 13, which is connected inan axially fixed manner to the actuating button 8 of the operatingelement 6, move with the dosing member 16. The operating element 6, theentrainer 13 and the dosing member 16 move together in the distaldirection and in the process rotate about the longitudinal center axis50 on account of the second threaded connection 18.

Via the rotationally fixed connection between the entrainer 13 and feedpart 20, the feed part 20 also rotates with respect to the upper housingpart 3. Via the first threaded connection 25, the feed part 20 alsomoves in the distal direction. The slide 19 likewise moves in the distaldirection, since the slide 19 is connected in a rotationally fixedmanner to the dosing member 16. The slide 19 and the feed part 20 alsomove with a combined rotary and longitudinal movement, wherein thedistances that the slide 19 and the feed part 20 cover in the directionof the longitudinal center axis 50 are fixed via the first threadedconnection 25 and via the third threaded connection 21, respectively.Provision can also be made for the slide 19 to be connected to thedosing member 16 via a third threaded connection and to be connected ina rotationally fixed manner to the housing part 3.

FIG. 3 shows the injection device 1 following the setting of a dose ofinjection fluid that is not intended by the manufacturer. The dosingmember 16 is located in an intermediate position 74 which will beexplained in more detail in the following text.

FIGS. 4 and 5 show the injection device 1 following the setting of anintended quantity of injection fluid to be ejected. The feed part 20 hasmoved by a first travel (a) in the distal direction. Following thesetting of the quantity of injection fluid to be ejected, the end sideof the feed part 20 has moved away from the stop 28 by the first travel(a). The operating element 6 having the adjustment sleeve 7 and theactuating button 8 has moved in the distal direction by a second travel(b). The second travel (b) is measured in the embodiment between theproximal end side of the adjustment sleeve 7 and the distal end side ofthe housing part 3. The second travel (b) is much greater than the firsttravel (a). In the embodiment, the second travel (b) is a multiple ofthe travel (a), for example about three times the travel (a). Thedifferent travels (a) and (b) result from different pitches of the firstthreaded connection 25 and of the second threaded connection 18. Thedosing member 16 has also moved in the distal direction by the secondtravel (b). The slide 19 has moved in the distal direction by a thirdtravel (c). The travel (c) can be the same size as the travel (a).However, provision can also be made for the travel (c) to be greaterthan the travel (a). The third travel (c) is indicated in FIG. 5 at theproximal end side of that portion of the slide 19 that bears the thread,specifically opposite the position of the end side in FIG. 2. During thesetting of the quantity of injection fluid to be ejected, the spring 82was tensioned. In the process, the spring 82 was elongated by the secondtravel (b). At the same time, the ends 83 and 84 of the spring 82 thatare shown in FIG. 8 were rotated about the longitudinal center axis 50with respect to the housing 2 on account of the rotation of the dosingmember 16.

The maximum quantity of injection fluid to be set is defined by thedistance by which the actuating button 6 and the dosing member 16 canmove in the distal direction. This distance is limited by a stop 27(FIG. 5) formed between the dosing member 16 and the slide 19. As FIG. 4shows, the dosing member 16 has, at its proximal end, an inwardlydirected ledge 41. A latching rim 42 on the slide 19 engages behind thisledge 41 in the axial direction. With the latching rim 42, the ledge 41forms the stop 27. As soon as the latching rim 42 bears against theledge 41, the maximum settable quantity of injection fluid has beenachieved. The spacing between the ledge 41 and the latching rim 42 inthe state, shown in FIGS. 1 and 2, of the injection device 1 correspondsto the second travel (b) minus the first travel (a).

As FIG. 6 shows, the first housing part 3 has a latching depression 37which is formed in a circumferential manner in the embodiment. A catch36 that projects radially outwards and is formed on the internal tube 17projects into the latching depression 37, the catch 36 securing theinternal tube 17 in the housing part 3 in the direction of thelongitudinal center axis 50 of the injection device 1. At its proximalend, the internal tube 17 bears against a shoulder 76 of the housingpart 3. In order to secure the rotary position, the internal tube 17 hasan outwardly projecting peg 48 which latches at the housing part 3adjacently to the window 9.

FIG. 6 also shows the support of the compression spring 15. Thecompression spring 15 is supported by way of its proximal end against ashoulder 32 of the dosing member 16 and by way of its distal end againsta rim 39 formed on the entrainer 13. The rim 39 projects outwardly froma sleeve-like portion of the entrainer 13. Adjacently to the rim 39, anexternal toothing 38 is arranged on the entrainer 13 at the distal sideof the rim 39. The external toothing 38 cooperates with an internaltoothing (not shown) on the adjustment sleeve 7 and forms the coupling14 with the latter. In the non-actuated position, shown in FIG. 6, ofthe actuating button 8, the coupling 14 is closed and establishes arotationally fixed connection between the entrainer 13 and an adjustmentsleeve 7. The compression spring 15 pushes the entrainer 13 in thedirection of the closed position of the coupling 14. As a result, theactuating button 8 is pressed in the direction of its distal position71.

After the dose to be injected has been set, an injection can beinitiated. To this end, the actuating button 8 is pressed in thedirection of the arrow 77 in FIG. 5, that is, in the proximal direction.As a result, the actuating button 8 moves into the adjustment sleeve 7,counter to the force of the compression spring 15, in the direction ofthe longitudinal center axis 50, until the actuating button 8 bearsagainst a stop 78 on the adjustment sleeve 7. FIG. 7 shows the actuatingbutton 8 in its second, proximal position 72. In this position, theexternal toothing 38 of the entrainer 13 has moved out of the region ofthe adjustment sleeve 7. As a result, the adjustment sleeve 7 isrotatable with respect to the entrainer 13 and the actuating button 8.The coupling 14 is open. When the actuating button 8 continues to bepressed in the direction of the arrow 77 in FIG. 5, the dosing member 16is pushed into the internal tube 17 and in the process moves in theproximal direction. In this case, the dosing member 16 rotates onaccount of the second threaded connection 18. On account of the rotationof the dosing member 16, the slide 19 is also rotated and as a resultmoves in the proximal direction. The rotation of the dosing member 16with respect to the housing 3 is supported by the spring 82. The slide19 has a driving ledge 62, which bears against a driving ledge 63 of thefeed part 20. Via the driving ledges 62 and 63, the slide 19 presses,during its movement in the proximal direction, against the feed part 20and moves the latter likewise in the proximal direction. The feed part20 is connected in a rotationally fixed manner to the entrainer 13,which is connected in an axially fixed manner to the non-rotatingactuating button 8. The rotation of the feed part 20 is prevented by thelatching device 26, which has been positioned in a latching positionduring the setting of the dose. As a result, the rotating slide 19cannot rotate the feed part 20 along with it. Since the feed part 20does not rotate and the dosing piston 22 is also connected in arotationally fixed manner to the housing part 3 via the piston rod ring30, the feed part 20 and the dosing piston 22 are connected fixedlytogether and move together in the proximal direction, until the feedpart 20 bears against the stop 28 and the set quantity of injectionfluid has been ejected in its entirety from the container.

The injection device 1 is intended to inject defined doses of injectionfluid. The dosing member 16 has at least one injection position 73,shown in FIG. 4, in which a structurally defined, intended quantity ofinjection fluid is set. The latching device 26 latches in latchingpositions 73. The dosing member 16 can also be positioned in at leastone intermediate position 74, which is shown in FIG. 3. In anintermediate position 74 of the dosing member 16, a non-intendedquantity of injection fluid is set. The latching device 26 does notlatch in intermediate positions 74 of the dosing member 16. Ifnon-intended doses of injection fluid are set, the dosing member 16 isrestored into the next lowest injection position 73 or the zero position85 by the spring 82 as soon as the user releases the adjustment sleeveis 7.

As FIG. 6 shows, the internal tube 17 of the housing 7 is constructedfrom a proximal part 46 and a distal part 47, which are connectedfixedly together. The internal tube 17 can also be produced in onepiece. However, this makes the internal tube 17 much more complicated toproduce. In order to further simplify production, it can be advantageousto form the internal tube 17 from more than two individual parts. AsFIG. 8 shows, the spring 82 acts between the distal part 46 of theinternal tube 17 and the dosing member 16. In this case, a first end 83of the spring 82 is fixed to the dosing member 16 and a second end 84 isfixed to the proximal part 46 of the internal tube 17. The ends 83 and84 are in this case mounted advantageously in corresponding recesses inthe dosing member 16 and proximal part 46.

FIGS. 9 to 27 show the components of the injection device 1 in detail.FIGS. 9 to 11 show the entrainer 13. For connection to the actuatingbutton 8, the entrainer 13 has, at its distal end, internal latchingelevations 35, which engage behind a latching rim 34, shown in FIG. 6,that is formed on a connecting piece 33 of the actuating button 8, andas a result connect the actuating button 8 to the entrainer 13 in theaxial direction. In the embodiment, the sleeve-like entrainer 13 has onits inner circumference four guiding ribs 40 that extend in the axialdirection. The guide ribs 40 match longitudinal grooves 64, shown inFIG. 22, in the feed part 20 and engage therein. The guide ribs 40establish, with the longitudinal grooves 64, the rotationally fixedconnection between the entrainer 13 and the feed part 20. The guide ribs40 are freely movable in the longitudinal grooves 64 in the direction ofthe longitudinal center axis 50 of the injection device 1.

FIGS. 12 to 14 show the dosing member 16, which is also referred to asscale tube or setting member. The dosing member 16 is formed in asleeve-like manner and has an external thread 44 on its outercircumference. The external thread 44 is configured as a grooveextending helically around the outer circumference of the dosing member16. As its distal end, the dosing member 16 bears a connecting contour43 which is formed from hook- and ramp-like elements, which establish arotationally fixed connection to the adjustment sleeve 7. As FIGS. 13and 14 show, the dosing member 16 has, at its proximal end, two guidegrooves 45 which extend parallel to the longitudinal center axis 50. Theguide grooves 45 are arranged opposite one another and cooperate withlongitudinal ribs 59 on the slide 19, which are shown in FIGS. 19 and21. Via the longitudinal ribs 59, which are guided in the longitudinalgrooves 45, a rotationally fixed connection is produced between thedosing member 16 and the slide 19. The longitudinal ribs 59 are freelymovable in the guide grooves 45 in the direction of the longitudinalcenter axis 50, such that the slide 19 is movable with respect to thedosing member 16 in the direction of the longitudinal center axis 50.

FIGS. 15 to 17 show the internal tube 17. The internal tube 17 isembodied in two parts and includes the proximal part 46 and the distalpart 47, which are connected fixedly together. Arranged in the distalpart 47 of the internal tube 17 is an internal thread 49, which isformed from a rib extending spirally around the inner circumference. Theinternal thread 49 is formed by a single thread. Provision can be madeto form the internal thread 49 only from one or more sections of athread. The internal thread 49 cooperates with an external thread 44 ofthe dosing member 16 and brings about an axial movement of the dosingmember 16 upon rotation of the dosing member 16. Formed in the proximalpart 46 of the internal tube 17 is an internal thread 51, whichcooperates with an external thread 61, shown in FIG. 18, of the slide19. With the external thread 61, the internal thread 51 forms the thirdthreaded connection 21. Longitudinal ribs 52 follow on the proximal sideof the internal thread 51. As FIG. 27 shows, a total of two longitudinalribs 52 are provided in the embodiment, the longitudinal ribs 52 beingarranged more or less opposite one another. With the two mutuallyopposite catches 67 of the feed part 20, the longitudinal ribs 52 definethe latching positions of the latching device and thus the injectionpositions 73. In the embodiment, the two injection positions 73 are atan angular spacing α of 180°. The angular spacing α is advantageously atleast about 30°, in particular at least about 45°, particularlyadvantageously at least 60°. In the circumferential direction, thelongitudinal ribs 52 are at an angular spacing β, shown in FIG. 27,which is somewhat less than 180° in the embodiment, for example about160° to 175°. The angular spacing β corresponds to the angular range inwhich the dosing member 16 can be positioned in intermediate positions74 between two injection positions 73 or an injection position 73 and azero position 85. Advantageously, the latching device 26 does not exertany force on the feed part 20 and thus on the dosing member 16 in thisangular range. A different number of longitudinal ribs 52 and/or catches67 may also be advantageous. For example, provision can be made of fourlongitudinal ribs 52 and two catches 67, which are arranged such that anangular spacing α of 90° is produced between the injection positions 73.

In the embodiment, the longitudinal ribs 52 and the catches 67 areconfigured such that it is not possible to rotate the operating element6 back out of the latching position into a position which is assigned toa smaller quantity of injection fluid. However, provision can also bemade for the shape of the longitudinal ribs 52 and catches 67 to allowthe operating element 6 to be rotated back, for example by a symmetricalconfiguration in the circumferential direction.

As FIG. 17 shows, a centering rim 58 projects in the proximal directionof the proximal end of the internal tube 17. The centering rim 58projects into a proximal opening in the housing part 3 and ensures afirm fit of the internal tube 17 in the housing part 3. On the proximalside of the internal tube 17, holding connecting pieces 56 furthermoreproject in the proximal direction, latching rims 57 that projectradially inward being integrally formed on the proximal end of theholding connecting pieces 56. The latching rims 57 cooperate withlatching rims 79 of the piston rod ring 34, which is shown in FIG. 5.The latching rim 79 provides, with the latching rim 57, axial securingfor the piston rod ring 30. As FIG. 5 shows, the second compressionspring 31 pushes the piston rod ring 30 into its proximal position untilthe latching rim 79 bears against the latching rim 57. In this position,the user can rotate the housing part 3 with respect to the piston rodring 30 in order to move the dosing piston 22 in the distal direction.This is provided for changing a container for injection fluid.

FIGS. 18 to 20 show the slide 19 in detail. At its distal end, the slide19 has the latching rim 42. As FIGS. 18 and 19 show, the external thread61 is formed on an annular rib 60 which projects radially outward. Theslide 19 is also formed in a substantially sleeve-like manner.

FIGS. 21 to 24 show the feed part 20. At its proximal end, the feed part20 has two latching arms 66, which are shown in FIG. 24. At their freeends, the latching arms 66 each have a catch 67, which is directedradially outward. The latching arms 66 extend approximately in thecircumferential direction and are configured to be resilient in theradially outward direction. FIG. 22 shows an internal thread 65 which isformed at the proximal end of the feed part 20 and which cooperates withthe dosing piston 22. The internal thread 65 and the latching arms 65are arranged in the same longitudinal portion of the feed part 20.

As FIGS. 25 and 26 show, the piston rod 23 has an external thread 69which cooperates with the internal thread 65 of the feed part 20 andforms the first threaded connection 25 therewith. On its oppositelongitudinal sides, the piston rod 23 has flattened portions 68 whichcooperate with corresponding flattened portions of an opening 80, shownin FIG. 5, in the piston rod ring 30, in order to secure the rotaryposition of the piston rod 23. At its proximal end, the piston rod 23has a fastening groove 70, by way of which the piston disk 24 is held.At its distal end, the piston rod 23 has a stop 89. At the distal end ofthe piston rod 23, the external thread 69 ends in a contour which has,in the embodiment, a round cross section with a diameter which isgreater than the outside diameter of the external thread 69. Theproximal face of this contour forms the stop 89 with respect to theinternal thread 68 of the feed part 20. At the stop 89, the piston rod23 has, in the embodiment, a round cross section, the outside diameterof which corresponds more or less to the greatest outside diameter ofthe piston rod 23. As a result, the stop 89 cannot be screwed into theinternal thread 65 of the feed part 20. However, some otherconfiguration of the stop 89, which prevents screwing into the internalthread 65, can be advantageous. The stop 89 is arranged such that thestop 89 butts against the feed part 20 when the quantity of injectionfluid still present in the container is set. As a result, the usercannot set a dose which is greater than the remaining quantity ofinjection fluid present in the container.

FIG. 27 shows the arrangement of the feed part 20 in an intermediateposition 74 of the operating element 6, dosing member 16 and feed part20. The catches 67 are spaced apart from the longitudinal ribs 52. Thespring 82 (FIG. 8) acts on the dosing member 16 in the direction of thezero position 85 of the dosing member 16. Via the coupling 14, which isclosed during the setting of the injection dose, and the entrainer 13,the spring 82 also acts on the feed part 20. The feed part 20 is loaded,in the direction of the arrow 86 shown in FIG. 27, in the direction ofthe previous latching position of the catches 67. As soon as the userreleases the adjustment sleeve 7, for example in order to press theoperating button 8 and inject a dose, the dosing member 16 and the feedpart 20 are restored into the previous intended position, which isassigned to the next lowest intended dose or no dose of injection fluid,on account of the force of the spring 82. In the process, the feed part20 rotates in the direction of the arrow 86. Intended positions are inthis case injection positions 73 or the zero position 85. Since it isnot possible to set a non-intended quantity of injection fluid, theejection of a non-intended quantity of injection fluid is prevented.

If the operating element 6 and also the feed part 20 are rotatedfurther, the catches 67, after overcoming the longitudinal ribs 52,which form the latching device 26 with the catches 67, pass behind thelongitudinal ribs 52 in the direction of rotation 87. The direction ofrotation 87 is the direction of rotation in which the feed part 20 andthe dosing member 16 rotate during the setting of the dose of injectionfluid. The longitudinal ribs form, at their sides that are located atthe front in the direction of the arrow 86, latching elements 53 atwhich the catches 67 latch. If the catches 67 bear against the latchingelements 53 of the longitudinal ribs 52, the latching device 26 islatched, and the arrangement is in an intended injection position 73.Further automatic movement of the feed part 20 in the direction of thearrow 86 on account of the force of the spring 82 is avoided by theabutment of the catches 67 against the latching elements 53. The usercan press the operating button 8 and inject the set dose. The ejectionof the set quantity of injection fluid is supported by the spring 82. Atthe longitudinal ribs 52, the catches 67 are guided in this caseparallel to the longitudinal center axis 50 of the injection device 1.As a result, the longitudinal ribs 52 ensure that the feed part 20cannot rotate about the longitudinal center axis 50 during the injectionof a dose and as a result reduce the quantity of injection fluid to beejected.

At their sides that are located at the front in the direction ofrotation 87, the longitudinal ribs 52 each have a slope 88, the slopes88 deflecting the catches 67 radially inward and thus making it easierto overcome the longitudinal ribs 52. The slopes 88 exert a forcecounter to the direction of rotation 87 on the catches 67 and thus onthe feed part 20 and the dosing member 16. In positions of the dosingmember 16 in which the catches bear against the slopes 88, the feed part20 is restored counter to the direction of rotation 87, on account ofthe force exerted by the latching device 26, until the catches 67 nolonger bear against the slopes 88 when the user does not exert anopposing force on the feed part 20. At the angular spacing β between thelongitudinal ribs 52, the catches 67 are at a spacing from the proximalpart 46 of the internal tube 17 and are not in contact with the proximalpart 46. Advantageously, the inner circumference of the proximal part 46extends in this region in a circular arc about the longitudinal centeraxis 50. In this region, the latching device 26 does not exert any forceon the feed part 20 or the dosing member 16. The restoration of the feedpart 20 and of the dosing member 16 into an injection position 73 or thezero position 85 takes place in this region exclusively on account ofthe force of the spring 82. The embodiment shows an injection device 1in which only a single defined quantity of injection fluid can beejected from the container. This quantity is reached when the operatingelement has been rotated through 180°. However, provision can also bemade for a plurality of injection positions 73, which are assigned todifferent quantities of injection fluid, to be possible.

FIGS. 29 to 70 show an embodiment of an injection device 101. Theinjection device 101 has a housing 102 having an upper housing part 103,on which a holder 4 is fixed. Identical reference signs to those in theprevious figures in this case identify identical elements. Arranged atthe distal end of the upper housing part 103 is a control element 106which comprises an adjustment sleeve 107 and an actuating button 108. InFIG. 29, the injection device 101 is in its zero position 185. The upperhousing part 103 has a window 109, through which a scale 110 is visible.In the zero position 185, the scale shows a “0” in the embodiment. Theactuating button 108 is in its distal position 171 in FIG. 29.

FIG. 30 shows the structure of the injection device 101 in detail. FIG.30 also shows the container 104 inserted into the holder 4, the pistondisk 24 of the dosing piston 22 bearing against the stop 105 of thecontainer 104. The injection device 101 has a piston rod ring 130, inwhich the piston rod 23 is guided in a rotationally fixed manner. Viathe piston rod ring 130, the piston rod 203 is held in a rotationallyfixed manner with respect to the housing 102. The piston rod 23 projectsthrough an opening 180 in the piston rod ring 130. The injection device101 shown is shown in an embodiment in which the user obtains the devicewith the container 104 already inserted, and in which the user disposesof the injection device 101 together with the container 104 when thecontainer 104 is empty. Replacement of the container 104 is notintended. The holder 4 is fixedly connected to the upper housing part103, for example non-releasably snap-fastened to or glued in place inthe latter. The piston rod ring 130 is secured in the upper housing part103 in the axial direction, that is, in the direction of thelongitudinal center axis 50, by the holder 4. The piston rod ring 134 isfurthermore held in a rotationally fixed manner in the housing 103, asis described in more detail in the following text.

The injection device 101 has a feed part 120, which is connected to thepiston rod 23 via a first threaded connection 125. Arranged at theproximal end of the feed part 120 is a latching device 126. The latchingdevice 126 is formed between the piston rod ring 130 and the feed part120. The feed part 120 is connected in a rotationally fixed manner to anentrainer 113. The entrainer 113 is connected in a rotationally fixedmanner to the actuating button 108. In the embodiment, the entrainer 113is integrally formed on the actuating button 108, that is, formed in onepiece with the actuating button 108.

A slide 119 bears against the feed part 120, the slide 119 acting on thefeed part 120 in the proximal direction. The slide 119 is connected tothe upper housing part 103 via a second threaded connection 121. Thesecond threaded connection 121 is formed at an inwardly projecting rim122 of the upper housing part 103. The slide 119 is connected in arotationally fixed manner to a dosing member 116. The dosing member 116is formed in one piece with the adjustment sleeve 107 and forms asetting part 112 with the latter. The setting part 112 is mounted in thehousing 102 in a rotatable but axially fixed manner. To this end, thesetting part 112 has, on the dosing member 116, a rim 117 that projectsradially outward and latches at the housing 102, as is described in moredetail in the following text. At its proximal side, the rim 117 has abevel 118 to make assembly easier. The scale 110 (FIG. 29) has beenapplied to the dosing member 116. During the setting of a quantity ofinjection fluid to be ejected, the adjustment sleeve 117 can be rotatedthrough less than one revolution, such that each value on the scale 110is assigned a clear quantity of injection fluid. In the embodiment, theadjustment sleeve 107 is rotatable through half a revolution.

The adjustment sleeve 107 is open at its distal end. The actuatingbutton 108 is held in an axially movable manner in the adjustment sleeve107. The actuating button 108 has a rim 123 which projects into theadjustment sleeve 170. Formed between the rim 123 and the adjustmentsleeve 107 is a coupling 114. In the distal position 171, shown in FIGS.29 and 30, of the actuating button 108, the coupling 114 is closed andconnects the actuating button 108 in a rotationally fixed manner to theadjustment sleeve 107. The actuating button 108 has a cylindricalconnecting piece 111, which is arranged in the radial direction betweenthe entrainer 113 and the rim 123. The end side of the connecting piece111 forms a stop 178, which cooperates with a shoulder 132 of thesetting part 112 and, together with the shoulder 132, fixes the proximalposition of the actuating button 108. Arranged on the outer side of theconnecting piece 111 is a compression spring 115, which pretensions theactuating button 108 into its distal position 171.

FIGS. 31 and 32 show the injection device 108 after the maximum dose hasbeen set. In the window 109, the scale 110 shows the number “4”. In thisposition, the injection device 101 is in an injection position 173, inwhich an intended quantity of injection fluid has been set. As FIG. 32shows, the coupling 114 continues to be closed. The actuating button 108is in its distal position 171. In order to set the quantity of injectionfluid to be ejected, the adjustment sleeve 107 has been rotated throughhalf a revolution in the clockwise direction with respect to the housing102 from the position shown in FIGS. 29 and 30. In the process, thedrive 113 has rotated the feed part 120. On account of the firstthreaded connection 125, the feed part 120 has moved in the distaldirection, specifically by a first travel (d). The dosing member 116 hascarried along and rotated the slide 119. Via the second threadedconnection 121, the slide 119 has moved in the distal direction by asecond travel (e), which advantageously corresponds to the first travel(d). Upon rotation of the adjustment sleeve 107, the feed part 120rotates with respect to the housing part 103, with the result that thelatching device 126 produces palpable and audible clicks.

In order to eject the set quantity of injection fluid, the actuatingbutton 108 has to be moved in the proximal direction in the direction ofthe arrow 77. The proximal direction 172 of the actuating button 108 isshown in FIG. 33. In this position, the coupling 114 is released. Theactuating button 108 has an external toothing 138, which is part of thecoupling 114. The external toothing 138 on the actuating button 108 hasmoved in the proximal direction from the region of the counterparttoothing on the adjustment sleeve 107 during the movement of theactuating button 108. As a result, the adjustment sleeve 107 isrotatable with respect to the actuating button 108. The coupling 114 isreleased. The actuating button 108 can be pressed until the stop 178bears against the shoulder 132 of the dosing member 116. The stop 178 isconfigured such that the friction between the dosing number 116 and theactuating button 108 is low. To this end, a rounded contour is providedon the connecting piece 111 in the embodiment.

As FIGS. 34 to 36 show, a spring 182, which is configured as a torsionspring, acts between the dosing member 116 and the piston rod ring 130that is held in a manner fixed to the housing. In the zero position 185shown in FIGS. 34 to 36, the spring 182 has preferably already beenpre-tensioned. This ensures that the spring 182 can keep the injectiongoing right to the end, that is, can push the stopper 105 in thecontainer 104 into the desired end position. If the adjustment sleeve107 is rotated in the clockwise direction with respect to the piston rodring 130, the spring 182 is tensioned further. The latching device 126prevents the adjustment sleeve 107 from rotating back into the zeroposition 185 after each overcome catch. As soon as the desired dose hasbeen set, the actuating button 108 should be pressed. As a result, thecoupling 114 is released and the adjustment sleeve 107 is rotated backinto its zero position 185 by the spring 182. The rotary movement of thesetting part 112 with the dosing member 116 causes the slide 119 torotate with respect to the housing part 103 and thus brings about anaxial movement of the slide 119 in the proximal direction, specificallyby the travel (e), via the second threaded connection 121. As FIG. 32shows, the slide 119 has a driving ledge 162, which cooperates with adriving ledge 163 of the feed part 120 and carries along the feed part120 in the proximal direction. In the process, the slide 119 pushes thefeed part 120 by the first travel (d). The feed part 120 is supported inthe circumferential direction in this case via the latching device 126,such that the feed part 120 cannot rotate. Since the piston rod 23 isheld in a rotationally fixed manner in the piston guide 130, the pistonrod 23 is moved in the proximal direction and injects the set quantityof injection fluid out of the container 104 via the stopper 105.

As FIGS. 34 to 36 show, a first end 183 of the spring 182 is mounted inthe rim 117 of the dosing member 116. A second end 184 of the spring 182is held on the piston rod ring 130. As the figures show, the piston rodring 130 has two arms 133 and 134 which extend in a distal, axialdirection on opposite sides of the piston rod ring 130. The first arm133 has a slot 137, in which the second end 184 of the spring 182 isguided. Via the piston rod ring 130, the second end 184 of the spring182 is connected in a rotationally fixed manner to the housing 102.During the setting of a dose, the spring 182 is tensioned, since thefirst end 183 is rotated with respect to the second end 184 that is heldin a manner fixed to the housing. After a dose has been set, thearrangement is held in an injection position 173 via the latching device126 until the user releases the coupling 114 by pressing the actuatingbutton 108. Once the coupling 114 has been released, the spring 182rotates the setting part 112 back into the zero position 184. Thus, theslide 119 is also screwed into the zero position 185 and in the processpushes the feed part 120 and thus the piston rod 23 in the proximaldirection, such that the set quantity of injection fluid is ejected fromthe container 104.

FIGS. 37 to 42 show the configuration of the setting part 112 in detail.The setting part 112 is formed in a substantially cylindrical manner andhas a portion with an enlarged outside diameter, which forms theadjustment sleeve 107, and an adjoining region with a reduced outsidediameter, which forms the dosing member 116. The rim 117 is adjoined bya connecting piece 143, which has the guide grooves 145 for connectingin a rotationally fixed manner to the slide 119. In the embodiment, twomutually opposite guide grooves 145 are provided. Some other number andarrangement of guide grooves 145 can also be expedient, however. Thespring 182 is guided at the outer circumference of the connecting piece143, as shown in FIG. 34. As FIG. 40 shows, the rim 117 has an opening144 in which the first end 183 of the spring 182 is mounted.

As FIG. 39 shows, a single latching tooth 146 is arranged on the innerside of the adjustment sleeve 107, the latching tooth 149 cooperatingwith the external toothing 138 of the actuating head 108. A largernumber of latching teeth 146 can also be provided, however. Since only asingle latching tooth 146 is provided, the actuating button 108 can bemounted easily in the adjustment sleeve 107 by axial insertion andlatching behind the latching tooth 146. As FIG. 46 shows, the actuatingbutton 108 has, on the distal side of the external toothing 138, a rim139 which latches behind the latching tooth 146. In this way, theactuating button 108 is secured in the adjustment sleeve 107 in theaxial direction.

FIGS. 38, 41 and 42 show the scale 110. The scale 110 shows a zeroposition 185, indicated by “0”, and four injection positions 173,indicated by “1”, “2”, “3”, and “4”. The injection positions 173 arearranged at equal spacings from one another.

FIGS. 43 to 45 show details of an embodiment of a dosing member 116′.The dosing member 116′ has a scale 110′ with a zero position 185indicated by “0” and a single injection position 173, which isidentified by “1”. In the case of an injection device 101 having thedosing member 116′, only a single, structurally defined quantity ofinjection fluid to be ejected can be set.

As FIGS. 46 to 49 show, the entrainer 113 has, on its inner side, guideribs 140, which serve for the rotationally fixed connection to the feedpart 120. In the embodiment, four guide ribs 140 that are distributedregularly around the inner circumference are provided. As FIG. 48 inparticular shows, the rim 123 is shorter in the axial direction than theconnecting piece 111, and the entrainer 113, which is arranged withinthe connecting piece 111, is longer than the connecting piece 111.

FIGS. 50 to 53 show the piston rod ring 130. The piston rod ring 130 hasa ledge 147, against which the holder 4 bears in the mounted state andfixes the piston rod ring 130 in the housing 102 in the axial direction.As FIGS. 50 and 53 show, the piston rod ring 130 has a toothing on itsinner circumference, the toothing being formed by a plurality oflongitudinal ribs 152. The longitudinal ribs 152 each have a latchingelement 153 on one side and a slope 188 on the opposite side. Thelongitudinal ribs 152 are formed in an asymmetric manner. The latchingelements 153 are oriented approximately in the radial direction withrespect to the longitudinal center axis 50. In this way, it is notpossible to rotate back into the next lowest injection position from aninjection position which has already been set. However, the latchingelements 153 can also be configured such that it is possible to rotateback. The latching elements 153 should be configured such that thelatching elements 153 cannot be overcome simply as a result of thetorque applied by the spring 182. In the embodiment, eight latchingelements 153 are arranged in a manner distributed regularly around theinner circumference of the piston rod ring 130. A different number oflatching elements 153 can also be advantageous in order to be able toset desired defined quantities of injection fluid.

A region in which the inner wall of the piston rod ring 130 extends inthe form of a circular arc around the longitudinal center axis 50 isarranged between each of the longitudinal ribs 152. As FIG. 53 shows,the piston rod ring 130 has the opening 180 for fixing the Piston rod 23in a rotationally fixed manner. For rotationally fixed fixing, theopening 180 has side walls 181 which extend in a rectilinear manner. AsFIGS. 51 and 52 show, the second arm 134 is formed in a much shortermanner than the first arm 133 in the axial direction. Formed on thefirst arm 133 are stops 135 and 136 with which the slide 119 cooperates.The second arm 134 does not project into the region of the stops of theslide 119.

FIGS. 54 and 55 show the configuration of the piston rod ring 130′ foran injection device 101 in which only a single dose can be set and whichcan have the dosing member 116′ from FIGS. 43 to 45. As FIGS. 54 and 55show, two longitudinal ribs 152 are arranged opposite one another. Thelatching elements 153 and the slopes 188 are formed on the longitudinalribs 152. In the single injection position 173, a catch 167 (FIG. 59)latches at each latching element 153.

FIGS. 56 to 58 show the slide 119 in detail. The slide 119 has acylindrical portion 148 which has longitudinal ribs 159 on its outerside, the longitudinal ribs 159 projecting into the guide grooves 145 ofthe dosing member 116. In this way, the slide 119 is connected in arotationally fixed manner to the dosing member 116. On its distal side,the slide 119 has an annular rib 160 which has an external thread 161.The external thread 161 forms the second threaded connection 121 withthe internal thread 151, shown in FIG. 65, of the upper housing part103. Arranged between the annular rib 160 and the cylindrical portion148 which bears the longitudinal ribs 159 are two arms 129 and 131 whichproject radially outward. Formed on the first arm 129 is a first stop127, which cooperates with the first stop 135 of the first arm 133 ofthe piston rod ring 130 and defines the zero position of the injectiondevice 101 therewith. The second arm 131 has a second stop 128, whichdefines the maximum dose, that is, the maximum quantity to be set ofinjection fluid to be ejected, with the second stop 136 of the pistonrod ring 130. Between the zero position and the maximum dose, the slide119 is rotatable through half a revolution with respect to the pistonrod ring 130 in the embodiment. Other rotation ranges can also beadvantageous.

FIGS. 59 to 63 show the feed part 120 in detail. The feed part 120 has asleeve-like portion, which has longitudinal ribs 164 on its outer side.In the embodiment, four longitudinal grooves 164 are provided. The guideribs 40 of the actuating button 108 project into the longitudinalgrooves 164. In this way, the actuating button 108 and feed part 120 areconnected together in a rotationally fixed manner. On its proximal side,the feed part 120 has two latching arms 166 which each bear a catch 167at their free ends. The feed part 120 furthermore has, at its proximalend, an internal thread 165 into which the piston rod 23 is screwed,forming the second threaded connection 121 therewith. FIGS. 61 and 62also show the driving ledge 163 against which the driving ledge 162 ofthe slide 119 bears.

FIGS. 64 to 66 show the upper housing part 103. The upper housing part103 is formed in a sleeve-like manner and has the window 109 adjacentlyto its distal end. The inwardly projecting rim 122 has the internalthread 151. The upper housing part 103 has, on its inner side, alatching elevation 142, behind which the rim 117 of the setting part 112(FIGS. 37 to 40) latches.

As FIG. 66 shows, the rim 122 has two openings 141 arranged opposite oneanother. The arms 133 and 134 of the piston rod ring 130 (FIG. 50)project through the openings 141. In this way, the piston rod ring 130is held in the housing 102 in a rotationally fixed manner.

FIG. 67 shows the injection device 101 in an intermediate position 174,in which a non-intended quantity of injection fluid is set. Part of thenumber “3” of the scale 110 is discernible in the window 109. As FIG. 68shows, the catches 167 are located adjacently to slopes 188 in thisposition. The catches 167 are not latched at latching elements 153. Inthis position, the spring 182 exerts a force in the direction of thearrow 186 on the feed part 120 and rotates the feed part 120 until thecatches 167 bear against latching elements 153. The latching elements153 are spaced apart from one another in the circumferential directionby an angle γ of about 45° about the longitudinal center axis 50.Adjacent longitudinal ribs 152 are at an angular spacing δ from oneanother which can be for example from about 20° to about 40°. Theangular spacing 5 corresponds to the angular range in which the dosingmember 116 can be positioned in intermediate positions 174 between twoinjection positions 173 or an injection position 173 and the zeroposition 185. One intermediate position 174 is shown in FIG. 68. Inintermediate positions 174, the torsion spring 182 moves the feed part120 in the direction of the arrow 186 as soon as the user releases theadjustment sleeve 107, until the next lowest injection position 173 orthe zero position 185 has been reached. In order to position the feedpart 120 in an injection position 173, the user can also rotate the feedpart 120 further in the direction of the arrow 187 until the injectionposition 173 shown in FIGS. 69 and 70 has been reached. In thisposition, the catches 167 bear behind latching elements 153 and are heldcounter to the spring force (arrow 186 in FIG. 68). The feed part 120 isguided in the axial direction along the longitudinal ribs 152 by way ofthe catches 167 during the ejection of a set quantity of injectionfluid.

The injection device 101 is shown as a disposable injection device inwhich it is not possible to exchange the container 104. However, ratherthan the piston rod ring 130, use can also be made of a piston rod ring30 which is held in an axially movable manner on the upper housing partand allows the container 104 to be changed.

It is understood that the foregoing description is that of the preferredembodiments of the invention and that various changes and modificationsmay be made thereto without departing from the spirit and scope of theinvention as defined in the appended claims.

What is claimed is:
 1. An injection device defining a longitudinalcenter axis and comprising: a housing having a receptacle formed thereinfor a vessel for holding injection fluid; an operator-manipulatedelement for setting an injection dose; a dosing member configured to berotated about said longitudinal center axis relative to said housingwhen setting the injection dose; said dosing member having a zeroposition whereat no dose is set and at least one injection positionwhereat an intended dose of injection fluid is set; a feed part; alatching unit configured to act between said feed part and said housing;said feed part being rotatable about said longitudinal center axis forsetting an injection dose; said feed part further being connected tosaid dosing member in a rotationally fixed manner so as to rotatetherewith during the setting of the injection dose; said housing havingat least one longitudinal rib; said feed part being configured to movein the direction of said longitudinal center axis with respect to saidhousing during an ejection of the dose and to be guided on said at leastone longitudinal rib; said latching unit having at least one latchingelement being formed on said longitudinal rib; said latching unitincluding at least one latching position corresponding to said injectionposition; said dosing member being positionable in at least oneintermediate position whereat no intended dose of injection fluid isset; and, a spring configured to act between said dosing member and saidhousing so as to return said dosing member, when theoperator-manipulated element is unactuated, from said intermediateposition to said at least one injection position or said zero position.2. The injection device of claim 1, wherein said dosing member has aplurality of said injection positions whereat corresponding doses ofinjection fluid are set; and, said latching unit includes a plurality ofsaid latching positions corresponding to respective ones of saidinjection positions.
 3. The injection device of claim 2, wherein saidspring is tensioned during the setting of the injection dose.
 4. Theinjection device of claim 1, wherein said latching device applies noforce to said dosing member in said intermediate position.
 5. Theinjection device of claim 1, wherein: the injection device defines acircumferential direction; said dosing member has at least two injectionpositions; and, said at least two injection positions have an angularspacing (β, δ) of at least approximately 30° from each other in thecircumferential direction about the longitudinal center axis.
 6. Theinjection device of claim 1 further comprising: saidoperator-manipulated element being a multi-part element including anactuating button and an adjustment sleeve; said adjustment sleeve beingfixedly connected to said dosing member; an entrainer connecting saidactuating button to said feed part; and, said actuating button beingconfigured to be moved in the direction of the longitudinal center axisin the proximal direction of the injection device so as to ejectinjection fluid from said vessel.
 7. The injection device of claim 6further comprising: a coupling connecting said actuating button to saidadjustment sleeve; said actuating button having a first, distal positionand a second, proximal position; and, said coupling being configured toform a rotationally fixed connection between said entrainer and saidadjustment sleeve in said first, distal position of said actuatingbutton and to allow a rotation of said adjustment sleeve relative tosaid entrainer in said second, proximal position of said actuationbutton.
 8. The injection device of claim 1 further comprising: a firstthreaded connection configured such that a rotational movement of saidfeed part during a setting of the injection dose effects an axialmovement of said feed part causing said feed part to move in thedirection of the longitudinal center axis by a first positioningdistance (a, d).
 9. The injection device of claim 8, wherein said dosingmember is mounted so as to be rotatable and so as to be immovable in thedirection of the longitudinal center axis.
 10. The injection device ofclaim 8 further comprising: a slide; a second threaded connection havinga thread on said slide; said slide being configured such that arotational movement thereof causes a movement in distal direction alongsaid longitudinal center axis by a second positioning distance (e) atleast as long as said first positioning distance (d); said feed parthaving a first entraining shoulder; and, said slide having a secondentraining shoulder for coacting with said first entraining shoulder totransfer an axial movement of said slide in proximal direction to saidfeed part.
 11. The injection device of claim 8, wherein: said dosingmember is connected to said housing via a second threaded connection;said dosing member is configured such that a rotational movement of saiddosing member effects a movement of said dosing member and saidoperator-manipulated element in the direction of said longitudinalcenter axis by a second positioning distance (b); and, said secondpositioning distance (b) is greater than said first positioning distance(a).
 12. The injection device of claim 11, wherein: a third threadedconnection having a thread on said slide; said slide being configuredsuch that a rotational movement thereof causes a movement in distaldirection along said longitudinal center axis by a third positioningdistance (c) at least as long as said first positioning distance (a);said feed part having a first entraining shoulder; and, said slidehaving a second entraining shoulder for coacting with said firstentraining shoulder to transfer an axial movement of said slide inproximal direction to said feed part.